Illuminator.



` i The! 82316215 i @Tis A- Mrssrtorrsw YORK, rN; Y'.

specificati To a/ZZ whom iz" 11d/ay concern:

11a-tors having an incandescent electric lamp' erating therewith. l v

zen of the United States, residing atNew- York, in the county of New York and -State of Newl York, have invented certain new and useful Improvements in Illuminators, fof which the -following is -a specification.

This invention relates tocornposlte1llum1 v as a basis oi illumination and a reflector cop- The' bject of the inventionisto produce aul illumina'tor composed of a lamp and refiec-` tor, as stated, by which light-rays fromv the ilament of an incandescent electric lam can besodirected and commingledas to il uminate -a predeterminedarea, generally beneath the'lamp, by means of the composite struc- 1 ture of lamp and reflector to a greater extent than could be done bythe lamp alone and in such manner that the eyes of the user ma be l l protectedfrom radiantv rays and the llght 25 sipcl cial referencer-o their use 1n the combme or y softened and rendered agreeable to ,the eye.

The invention consists in the construction of the lamp-bulbxand the reflector with y, compositestructure and their combination in such structure.` vThe larnp-bulb is provided with a frosted or similar partially'reflective and partially diffusingsurface over a portion oi' its 4body and a clear or transparent .portion above the same. The reflector is constructed and arranged with such relation yto both parts of thela'rnp'as to give the de'-,

sire-d result in the diffusion, distribution, and

commin ling of the light-rays.

Incan escent lamp-bulbs are generally made bi pear shape with the filament -of a single or double loopform and about concentric Withthe curved large end ofthe bulb, because such bulbs have demonstrated their superiority in thelmatters. of cost, durability,

` Lamp-bulbs lhave been frosted and have been varnished in whole or in part with the object of softeniu' the Vlight-ra s passing through the froste surface.. "Soar as I am aware no special attempt has been made prior to-my mventicn to reflect thereflected vrays from the's'urface of frosted, glass ir `de'- vterrnined directions' andto commingle such Iraysfwith radiant rays and reflected rays con- `rolledy as to their direction by'reflecting-surweg n the drawings intended to illustrate the general features of nay'invention, Figure 1 is of ietters `Zlat'ent. Application vfiledl-Aprili),1905'. Serial No}\2f56,462.v

resented June'ie, 1906.

a* Sid@ elevati@ Ora-nf 'ineanaescnrimp-bult having a partially-frosted or-ground surfacel vand apartial surface ofclear glass'and a ree-course'of some li 'g 2 is a side elevation of alainp-bulb' nd a p ismaticreflector, the entire surfaceo the ing ilctor of prismatic glass shown inisection, i g

t-rays being indicated.

tion f a lamp-bulb and reflector of dierent v n dwin an uncovered transparent por-v tion of t a e bu b' under the reiiector. Fig. l is a side ele tion of a lamp-bulb and reflector of different form, thebulb being frosted in scallops@ Fig. 5 is asideelevationl of a lamp bulb with its frosted portioncarried Within b which is not covered by thereiiector b' round or frosted.' Fig. S'is aside eleva-X the reflector anda refiector shown -insectio'n and in'dicatin vthe course" of. somev light-rays. Figs. 6, 7, jan 8 areillustrative comparative diagrams showin outlines of fields` of'vil-lu mination under 'be-explained.' 1

Incandescent electric lamps as generally constructed throw the strongest lightside wise andthe Weakest light in u ward and? `downward direction. As these amps are-v most. if'requentlyhung as pendants and the light is mostly desired'in downward direction ses or. at about fort'yffive' degrees' from the verti 85'` cal, it .has beenquite common to use a reflector with sucha lamp to reflectl the light'downl"wardl Reflectors ci' metal or silvered glass place above the lamp can be used as elements in myombinatlon; `but as such reflec-` 9 tors cut ofl` all the light and leavethefceiling' dark I prefertouse'refleetors of prismatic glass which can bev constructed to reflect as much as'eighty-fivevper cent. of thev light, 4 'Y -v 'y rays,v but 'pass some rays which'iilluminate 95'." Y the outside of the reector. andthe wall forspace above the same. Re'iicctors of gorc'e lain or op'al 'glass 'ermit the passage c some are not eicient in directinglight in efinite ldirections and in' definite quantities. V

y In all common forms oi refiect'or consider-fl able light is absorbed.` For my. urpose prisl ymatic lass is. ent ofIight-rays,v Y Referring new to Fi' preferred as'being east absorb-4V light-raysand r ect some of the ra s, .but 1 f 10Q j incandescent lam bub trans arent' at its 'supper part,l and -indicates t e ound or frosted lower partofsaid bulb. VT 1e' frosted surfacema'- be obtainedb n ding',b etch- "in ,orbyt euse of vernis lle effect of the frosted or ground semifri" ncwnlnt sart.

o aque surface on the glass is'to someof y t e light to pass through theglass., but in ad1ffused or softened condition, and all direct View vof the filamentthroughftheground surface is 5'. cut off. ,By grinding Vor opa uin the lower part of the incandescent'lamp.A ul to ay plane somewhat 'highery than the widest diameter of the bulb and hanging a flaredoutde` flector over the.- bulb, so that its lower edge 'art of the bulb reach the reflector as usual.;

ome light-rays arey reflected by the .frosted surface ofthe bulb, and these may'berere'- flected by 4'the reflector either through the 'bulb or alongside thereof, as may be .c'altzuiv lated. 2o

-ing a prismatic outer surface, an

- genera is of the j radialprisms on the outersurface'of this re` 2 5- double reflecting prisms. To e most eflicient as reflectors, theprisms should be arranged with their flat faces about forty-five Y grees from radial lines emanating from the source of lightj. 1 l

'A filament of the usual and-preferred form throws out rays of light from all partsof its 'furfaceg For theA presentv I will only considerlightirays as emanating from the center 35 of the filament. Referring to Fig.y l, let-us suppose'theray c d' to radiate from the center lcfto thereflective surface d of thevreflector.`

.dtd this ra is reflected back in a line nearly --parallel wit the'line cd, and after passing through thefrosted surface B. of the bulb the ray emerges inthe direction e, but is softened and diffused-by passing through the'frosted glass. Of course there are direcrays which lpass 'in the' direction c e vand interinin'gl'e' with the'reflectedrays;

but a reflecting,.surfalce` J y y, vportion bf thedirect rays pass throuh the semi-opaque surface, some Taysare're aray, as cf., That part' of the ayfWhich is reflectedl at f is thrownibackytbwardgion the l reflector. The form. of they 'reflector deter`l `Inines 'the subsequent courseof the light-ray.

5g The reflector may be of ysuch form as tothrow 'such a reflected ray in "the direction h. Such a reflected ray is I nuch softer than a `radiant raywhich has been merely reflected from the reflector C-as,l for instance, the *rayzindli .of its prisms.

` `The reflector C, Fig. 1, of clear'cglass,

characterdescribed injUnited States Patent No.687,848,.December3,1901. The

flector are ofthe 'character frequentl termed acted thereby. Let us considerthecourse of such ofthe ray from m town depending. on the form -of the reflector as well as onl the inclination The"reflector", Fi 2, is of a forni to concentrate vthe reflecte rays downwardly in 7o large degree. The frosted surface B in thev same figure is -vextend ed `up'as far as the lower edgeof reflector C, so that in most `positions no direct' rays from the filament can reach the eye. The frosted surface B ma actas 75 a reflector for as much as one-half t ie light which reaches it, and light so reflected isin a different condition from that'of light reflected-from ordinary olished surfaces, the 4regfl'ectedays being a so softened. By increas- 8o ing or diminishing the area of the frostedsur- 'facedof the lamp more or lessV of the total amount of'light mayl be reflected and sof- Atened thereby. By changing the character of the prisms on'reflector C 'more or less o'fv 8 ..thev` light may be reflected by said reflector,

the rays not reflected passing throu h the re-'lr flector. By changin the formhof t 1e reflector-C the reflected li t-raysmay be more or less concentrated. y varying the distance 59o between the reflector andthebulb thereflected light-rays are projected from different parts of the reflector and the whole combination may be changed. :Thus in Fig. 5 the' direct ray o from one side of the filament en? 95 countersl the reflector C2- at p and is reflected downward toward 127. The ray 0^ is reflected in part from the frosted surface B2, reaches' the. reflector at p, and is directed in its softened condition to 1" tened b passing through the frosted surface B2, reac es 1"?. We have thus three different kinds or qualities of light about at the point r, and of course-'the same conditions exist ac# tuall at the point 1'. Now' ifthe reflector C2 ro 5 flector and by the form of the reflector their direction will bev changed, substantially as in- `no dicated in dotted lines.

4Referrin again to Fig 5,

1i h la' us follow' 'tfrays Tt om the point s on the filament.y

e direct ray .s s passes overthe frosted surface on the bulband under the reflector, i 15 but in such a direc-tion that it is largely lost` in space. The ra s .s2 from the saine oint isil in part reflects back to s on-the re ector and is then thrown downwardly'toward s* in 1a much more useful direction and in softened --|nac.

- From the above it Will be known that my combination of artly-frosted bulb and movk able reflector a ords verywide latitude inthe f control of the illuminating propertfesand rg. 'qualities of'an incandescent amp.

A. lam 'fbulb is ver?7 cheaply frosted-by etching, an a reate'r or ess proportion of the bulb maywbe.

l 'osted 'according to the character of-illu- "nation desired. rlhe reflector can be made'of 13o The direct ray 02, sof-` loo l l. full line` indicates the part of the surfacefof .the the concentration of heat'in such oase's,such` a lamp hasbutabouthalf the. life of an un- 5o i livedx. It has 7 este@ softened, as are'therays which pass throng Y fthe frosted glass.

l "g '1--Tli'e arrows in Fig. 3 and showthej' l `i i general or paramount directionoffthe reiiectrcs ed .lightrays due to y such gener-,al forms of re- `leotor, arranged in about'the illustrated re,- lation to a lamp-bulb ofthe formand charac-f tershow'n. The flaring reilector'oi Figffcan 1 be -made tof directfnearly all the ree'cted light-rays' outwardly between the lamp-bulb and -r'eiiector andvery few reflected rayswill downw ard. `Thusv modiiied as t'e conservethelife'of the lamp inthe diagram Fig. je the daediiii 'i in;

' about a transparent glass lam of thirty-twocandle poweryand the full -1ne 2findicates the. distribution-'off the same vlamp with a re.-

' f i Hector. .of 'the' form shown 'inf Fig. 5 applied' thereto. In Fig. 17 the dotted line indi. cates 4the outline of distribution fromA the same vpower-larrp, lower half frosted', and the same combined with the relectorfofFig.' '6,

combination of my'improved `-illuminator.`

ter illustrated, 'but itshould be understood thatf thev position ofthe illuminator may be bchanged.

It has beenicommon toeproduce: reflectors for ineandesc'ent?electricA lamps by silver-inge lamp. @wing to silvered lamp?, .Reiectjors have also been madeof metalplacedelose to the lamp, and for a like reasontlese lamps arealso shortbulbs with concave outer surface, as inFig. 12 of` Britishlatent No. 23,111 or 1895. `From thecollapse of hundreds of bulbs of oo n- .cave constructionfunder vacuum pressure l am convinced that such construction is not practical.

the lamp. 4'Under such circumstances the' filament of the lamp -will fj endurefmuch longerthanin the form vshown in' Fig. '2,by which the lrays are concentrated my inventionjmaybe' so dicates the outline of the-'distribution of light r i' greatest diameter of the bulb. Fig. 8 shows lines Zand 4 superposed, illu'strating' clearly thediiferences resulting from" a v ohangeiniithe elements constitutingfthn' yprisinatie I have're'ferred to the upper and lower ends i- 4o of thebulb, such. .being the usual operative portionoineandescent lamps ofthe. charac-y been'proposed to'niale lamp-y Myreflector-heretoforedescribed 4 v 6 o )cmg separate from and held ata lit-tie distance from thejIamp`bulb doesnot coucou# trate heat to a destructivedegree, and'ibulbs will-last aslo'ng inthe combination withtlie A reflectores lwithout a reflector. This is not y-truefof any reflector which -is inl contact with thebulb, so far as I know, unless provision is made for ventilation beween the bulb andre- 1. The combination, v'in an illuminator,of 4`ian' incandescent lamp-bulb having its upper 0 f Y Y ortion 'transparent and 'its lower portion wiiosted', 4andial separate reflector-a little removed from 'said.bulb, and surrounding the clear portion thereof, leaving the'frosted porof the reflector.l Y 4 moved from said bulb'rrosted at its lower end andi transparent above the frosting, and a separateand removable reflector-of" ris- 3. The-combination, in an-ill'uminator, of

tion of ,the bulb 'projecting below' the bottom .maticglass surrounding-the'elear end o 'the bulb andilaring' outwardbeyond thefwidest .part of the bulb.' v8s@ f anfinoandescent lamp-.bulbi frosted.` at its flower end and transparent above. the-frosting, Y .andaseparate and removable reiieotory o* prismatic glass; having its outer surface substaritiallyvv covered' with double 'reiiecting- 1 prisms, arrangedvabout the transparent end f ofthe .bulb andl a little removed from said vv*bulb andv klfrojecting outward Y. 4. The combination, inan illuminator, of

an electric lampibulbfhaving i-tslower part 'frosted andl its 'upper part transparenandza lclear glassv vreflector surrcuir'idi-ng'` the l art ofsaid bulb and alittle removed there omg-said reiectorhaving its outer suri facesubstantiallycovered'with doublerefiect-ji i l ing-prisms arranged radially," the lower edge y f of the` reflector viiaring beyond the largest diameter of the lamp and terminatingv above the plane of the frosted portion of the bulb. i f 5. The combination, in an illuminator, of-

`an ineandescentflamp bulb frosted at. itsl lowerend and-transparent above the frosting,-

andv a separate vand removable reflector of prismatic glass surrounding Ithe clear endof the bulb, and alittle removedjthe'refrom, said Iro reflector'flaring outwardly beyond the widest part ofthe lamp-bulb, so as to direct themayJorityor' the relectcdlight-iays away from. the lampbulb;,'

In testimony whereof I afiix my signature. inpresence o'ttwo'witncsses.

Uris. A. M i'eiirrp f 

